A handout photograph provided by Brian Kubicki of Costa Rican Amphibian Research Center on 26 April 2016 shows a “Crystal frog”, Hyalinobatrachium dianae (H. diane). This frog was discovered by US biologist Brian Kubicki and Costa Ricans Stanley Salazar and Robert Puschendorf in a rainy forest of Costa Rican caribbean after 40 years without notice of any new example of this kind. (Photo by Brian Kubicki/EPA/Costa Rican Amphibian Research Center)

A police officer has weapons blessed by a Hindu priest during the Vishwakarma Puja festival in the outskirts of Agartala, India, September 17, 2016. (Photo by Jayanta Dey/Reuters)

Hindu women apply “sindhur”, or vermillion powder, on the face of a woman after worshipping the idol of the Hindu goddess Durga on the last day of the Durga Puja festival in Chandigarh, India October 11, 2016. (Photo by Ajay Verma/Reuters)

A Black Pete interacts with children during the arrival of Sinterklaas, or Saint Nicholas, in Maassluis, Netherlands, Saturday, November 12, 2016. Sinterklaas and his helper Black Pete are at the center of a long-time controversy because Pete is often played by white people in blackface makeup. (Photo by Peter Dejong/AP Photo)

People follow king penguins exploring their outdoor pen, during a so-called “penguin parade”, when the animals walk outside their enclosure and the visitors can walk behind them, at Zurich's Zoo in Zurich, Switzerland January 28, 2017. (Photo by Arnd Wiegmann/Reuters)

Medieval jousters Luke Binks (L) and Andrew McKinnon pose for a photograph in Sydney, Australia, August 16, 2017 during a photo call for the World Jousting Championships to take place in Sydney on September 23 and 24. (Photo by Dan Himbrechts/Reuters/AAP)

Traffic enforcer Ramiro Hinojas, 51, wears a Santa Claus costume while directing motorists through traffic at an intersection in Pasay City, Metro Manila, Philippines on November 28, 2017. (Photo by Romeo Ranoco/Reuters)

Green Bay Packers' Johnathan Calvin rides a bike to NFL football training camp on July 27, 2017, in Green Bay, Wis. (Photo by Morry Gash/AP Photo)